/* *------------------------------------------------------------------ * Copyright (c) 2016 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *------------------------------------------------------------------ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define foreach_virtio_tx_func_error \ _(NO_FREE_SLOTS, "no free tx slots") \ _(TRUNC_PACKET, "packet > buffer size -- truncated in tx ring") \ _(PENDING_MSGS, "pending msgs in tx ring") \ _(INDIRECT_DESC_ALLOC_FAILED, "indirect descriptor allocation failed - packet drop") \ _(OUT_OF_ORDER, "out-of-order buffers in used ring") \ _(GSO_PACKET_DROP, "gso disabled on itf -- gso packet drop") \ _(CSUM_OFFLOAD_PACKET_DROP, "checksum offload disabled on itf -- csum offload packet drop") typedef enum { #define _(f,s) VIRTIO_TX_ERROR_##f, foreach_virtio_tx_func_error #undef _ VIRTIO_TX_N_ERROR, } virtio_tx_func_error_t; static char *virtio_tx_func_error_strings[] = { #define _(n,s) s, foreach_virtio_tx_func_error #undef _ }; static u8 * format_virtio_device (u8 * s, va_list * args) { u32 dev_instance = va_arg (*args, u32); int verbose = va_arg (*args, int); u32 indent = format_get_indent (s); s = format (s, "VIRTIO interface"); if (verbose) { s = format (s, "\n%U instance %u", format_white_space, indent + 2, dev_instance); } return s; } typedef struct { u32 buffer_index; u32 sw_if_index; vlib_buffer_t buffer; generic_header_offset_t gho; } virtio_tx_trace_t; static u8 * format_virtio_tx_trace (u8 * s, va_list * va) { CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *); virtio_tx_trace_t *t = va_arg (*va, virtio_tx_trace_t *); u32 indent = format_get_indent (s); s = format (s, "%U ", format_generic_header_offset, &t->gho); s = format (s, "%Ubuffer 0x%x: %U", format_white_space, indent, t->buffer_index, format_vnet_buffer, &t->buffer); s = format (s, "\n%U%U", format_white_space, indent, format_ethernet_header_with_length, t->buffer.pre_data, sizeof (t->buffer.pre_data)); return s; } static_always_inline void virtio_interface_drop_inline (vlib_main_t * vm, uword node_index, u32 * buffers, u16 n, virtio_tx_func_error_t error) { vlib_error_count (vm, node_index, error, n); vlib_buffer_free (vm, buffers, n); } static_always_inline void virtio_memset_ring_u32 (u32 * ring, u32 start, u32 ring_size, u32 n_buffers) { ASSERT (n_buffers <= ring_size); if (PREDICT_TRUE (start + n_buffers <= ring_size)) { clib_memset_u32 (ring + start, ~0, n_buffers); } else { clib_memset_u32 (ring + start, ~0, ring_size - start); clib_memset_u32 (ring, ~0, n_buffers - (ring_size - start)); } } static_always_inline void virtio_free_used_device_desc (vlib_main_t * vm, virtio_vring_t * vring, uword node_index) { u16 used = vring->desc_in_use; u16 sz = vring->size; u16 mask = sz - 1; u16 last = vring->last_used_idx; u16 n_left = vring->used->idx - last; u16 out_of_order_count = 0; if (n_left == 0) return; while (n_left) { struct vring_used_elem *e = &vring->used->ring[last & mask]; u16 slot, n_buffers; slot = n_buffers = e->id; while (e->id == (n_buffers & mask)) { n_left--; last++; n_buffers++; struct vring_desc *d = &vring->desc[e->id]; u16 next; while (d->flags & VRING_DESC_F_NEXT) { n_buffers++; next = d->next; d = &vring->desc[next]; } if (n_left == 0) break; e = &vring->used->ring[last & mask]; } vlib_buffer_free_from_ring (vm, vring->buffers, slot, sz, (n_buffers - slot)); virtio_memset_ring_u32 (vring->buffers, slot, sz, (n_buffers - slot)); used -= (n_buffers - slot); if (n_left > 0) { vlib_buffer_free (vm, &vring->buffers[e->id], 1); vring->buffers[e->id] = ~0; used--; last++; n_left--; out_of_order_count++; vring->flags |= VRING_TX_OUT_OF_ORDER; } } /* * Some vhost-backends give buffers back in out-of-order fashion in used ring. * It impacts the overall virtio-performance. */ if (out_of_order_count) vlib_error_count (vm, node_index, VIRTIO_TX_ERROR_OUT_OF_ORDER, out_of_order_count); vring->desc_in_use = used; vring->last_used_idx = last; } static_always_inline void set_checksum_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr, int is_l2) { if (b->flags & VNET_BUFFER_F_IS_IP4) { ip4_header_t *ip4; generic_header_offset_t gho = { 0 }; vnet_generic_header_offset_parser (b, &gho, is_l2, 1 /* ip4 */ , 0 /* ip6 */ ); hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x22; if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM) { hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); } else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM) { hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum); } /* * virtio devices do not support IP4 checksum offload. So driver takes care * of it while doing tx. */ ip4 = (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset); if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM) ip4->checksum = ip4_header_checksum (ip4); } else if (b->flags & VNET_BUFFER_F_IS_IP6) { generic_header_offset_t gho = { 0 }; vnet_generic_header_offset_parser (b, &gho, is_l2, 0 /* ip4 */ , 1 /* ip6 */ ); hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x36; if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM) { hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); } else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM) { hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum); } } } static_always_inline void set_gso_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr, int is_l2) { if (b->flags & VNET_BUFFER_F_IS_IP4) { ip4_header_t *ip4; generic_header_offset_t gho = { 0 }; vnet_generic_header_offset_parser (b, &gho, is_l2, 1 /* ip4 */ , 0 /* ip6 */ ); hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; hdr->gso_size = vnet_buffer2 (b)->gso_size; hdr->hdr_len = gho.hdr_sz; hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x22; hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); ip4 = (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset); /* * virtio devices do not support IP4 checksum offload. So driver takes care * of it while doing tx. */ if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM) ip4->checksum = ip4_header_checksum (ip4); } else if (b->flags & VNET_BUFFER_F_IS_IP6) { generic_header_offset_t gho = { 0 }; vnet_generic_header_offset_parser (b, &gho, is_l2, 0 /* ip4 */ , 1 /* ip6 */ ); hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; hdr->gso_size = vnet_buffer2 (b)->gso_size; hdr->hdr_len = gho.hdr_sz; hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; hdr->csum_start = gho.l4_hdr_offset; // 0x36; hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum); } } static_always_inline u16 add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif, virtio_if_type_t type, virtio_vring_t * vring, u32 bi, u16 free_desc_count, u16 avail, u16 next, u16 mask, int do_gso, int csum_offload, uword node_index) { u16 n_added = 0; int hdr_sz = vif->virtio_net_hdr_sz; struct vring_desc *d; d = &vring->desc[next]; vlib_buffer_t *b = vlib_get_buffer (vm, bi); struct virtio_net_hdr_v1 *hdr = vlib_buffer_get_current (b) - hdr_sz; int is_l2 = (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_PCI)); clib_memset (hdr, 0, hdr_sz); if (b->flags & VNET_BUFFER_F_GSO) { if (do_gso) set_gso_offsets (b, hdr, is_l2); else { virtio_interface_drop_inline (vm, node_index, &bi, 1, VIRTIO_TX_ERROR_GSO_PACKET_DROP); return n_added; } } else if (b->flags & (VNET_BUFFER_F_OFFLOAD_TCP_CKSUM | VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)) { if (csum_offload) set_checksum_offsets (b, hdr, is_l2); else { virtio_interface_drop_inline (vm, node_index, &bi, 1, VIRTIO_TX_ERROR_CSUM_OFFLOAD_PACKET_DROP); return n_added; } } if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0)) { d->addr = ((type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm, b) : pointer_to_uword (vlib_buffer_get_current (b))) - hdr_sz; d->len = b->current_length + hdr_sz; d->flags = 0; } else if (vif->features & VIRTIO_FEATURE (VIRTIO_RING_F_INDIRECT_DESC)) { /* * We are using single vlib_buffer_t for indirect descriptor(s) * chain. Single descriptor is 16 bytes and vlib_buffer_t * has 2048 bytes space. So maximum long chain can have 128 * (=2048/16) indirect descriptors. * It can easily support 65535 bytes of Jumbo frames with * each data buffer size of 512 bytes minimum. */ u32 indirect_buffer = 0; if (PREDICT_FALSE (vlib_buffer_alloc (vm, &indirect_buffer, 1) == 0)) { virtio_interface_drop_inline (vm, node_index, &bi, 1, VIRTIO_TX_ERROR_INDIRECT_DESC_ALLOC_FAILED); return n_added; } vlib_buffer_t *indirect_desc = vlib_get_buffer (vm, indirect_buffer); indirect_desc->current_data = 0; indirect_desc->flags |= VLIB_BUFFER_NEXT_PRESENT; indirect_desc->next_buffer = bi; bi = indirect_buffer; struct vring_desc *id = (struct vring_desc *) vlib_buffer_get_current (indirect_desc); u32 count = 1; if (type == VIRTIO_IF_TYPE_PCI) { d->addr = vlib_physmem_get_pa (vm, id); id->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz; /* * If VIRTIO_F_ANY_LAYOUT is not negotiated, then virtio_net_hdr * should be presented in separate descriptor and data will start * from next descriptor. */ if (PREDICT_TRUE (vif->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT))) id->len = b->current_length + hdr_sz; else { id->len = hdr_sz; id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; id->addr = vlib_buffer_get_current_pa (vm, b); id->len = b->current_length; } while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; b = vlib_get_buffer (vm, b->next_buffer); id->addr = vlib_buffer_get_current_pa (vm, b); id->len = b->current_length; } } else /* VIRTIO_IF_TYPE_[TAP | TUN] */ { d->addr = pointer_to_uword (id); /* first buffer in chain */ id->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz; id->len = b->current_length + hdr_sz; while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { id->flags = VRING_DESC_F_NEXT; id->next = count; count++; id++; b = vlib_get_buffer (vm, b->next_buffer); id->addr = pointer_to_uword (vlib_buffer_get_current (b)); id->len = b->current_length; } } id->flags = 0; id->next = 0; d->len = count * sizeof (struct vring_desc); d->flags = VRING_DESC_F_INDIRECT; } else if (type == VIRTIO_IF_TYPE_PCI) { u16 count = next; vlib_buffer_t *b_temp = b; u16 n_buffers_in_chain = 1; /* * Check the length of the chain for the required number of * descriptors. Return from here, retry to get more descriptors, * if chain length is greater than available descriptors. */ while (b_temp->flags & VLIB_BUFFER_NEXT_PRESENT) { n_buffers_in_chain++; b_temp = vlib_get_buffer (vm, b_temp->next_buffer); } if (n_buffers_in_chain > free_desc_count) return n_buffers_in_chain; d->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz; d->len = b->current_length + hdr_sz; while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { d->flags = VRING_DESC_F_NEXT; vring->buffers[count] = bi; b->flags &= ~(VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID); bi = b->next_buffer; b->next_buffer = 0; n_added++; count = (count + 1) & mask; d->next = count; d = &vring->desc[count]; b = vlib_get_buffer (vm, bi); d->addr = vlib_buffer_get_current_pa (vm, b); d->len = b->current_length; } d->flags = 0; vring->buffers[count] = bi; vring->avail->ring[avail & mask] = next; n_added++; return n_added; } else { ASSERT (0); } vring->buffers[next] = bi; vring->avail->ring[avail & mask] = next; n_added++; return n_added; } static_always_inline void virtio_find_free_desc (virtio_vring_t * vring, u16 size, u16 mask, u16 req, u16 next, u32 * first_free_desc_index, u16 * free_desc_count) { u16 start = 0; /* next is used as hint: from where to start looking */ for (u16 i = 0; i < size; i++, next++) { if (vring->buffers[next & mask] == ~0) { if (*first_free_desc_index == ~0) { *first_free_desc_index = (next & mask); start = i; (*free_desc_count)++; req--; if (req == 0) break; } else { if (start + *free_desc_count == i) { (*free_desc_count)++; req--; if (req == 0) break; } else break; } } } } static_always_inline uword virtio_interface_tx_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, virtio_if_t * vif, virtio_if_type_t type, int do_gso, int csum_offload) { u16 n_left = frame->n_vectors; virtio_vring_t *vring; u16 qid = vm->thread_index % vif->num_txqs; vring = vec_elt_at_index (vif->txq_vrings, qid); u16 used, next, avail; u16 sz = vring->size; u16 mask = sz - 1; u16 retry_count = 2; u32 *buffers = vlib_frame_vector_args (frame); clib_spinlock_lock_if_init (&vring->lockp); if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 && (vring->last_kick_avail_idx != vring->avail->idx)) virtio_kick (vm, vring, vif); retry: /* free consumed buffers */ virtio_free_used_device_desc (vm, vring, node->node_index); used = vring->desc_in_use; next = vring->desc_next; avail = vring->avail->idx; u16 free_desc_count = 0; if (PREDICT_FALSE (vring->flags & VRING_TX_OUT_OF_ORDER)) { u32 first_free_desc_index = ~0; virtio_find_free_desc (vring, sz, mask, n_left, next, &first_free_desc_index, &free_desc_count); if (free_desc_count) next = first_free_desc_index; } else free_desc_count = sz - used; while (n_left && free_desc_count) { u16 n_added = 0; virtio_tx_trace_t *t; vlib_buffer_t *b0 = vlib_get_buffer (vm, buffers[0]); if (b0->flags & VLIB_BUFFER_IS_TRACED) { t = vlib_add_trace (vm, node, b0, sizeof (t[0])); t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_TX]; t->buffer_index = buffers[0]; if (type == VIRTIO_IF_TYPE_TUN) { int is_ip4 = 0, is_ip6 = 0; switch (((u8 *) vlib_buffer_get_current (b0))[0] & 0xf0) { case 0x40: is_ip4 = 1; break; case 0x60: is_ip6 = 1; break; default: break; } vnet_generic_header_offset_parser (b0, &t->gho, 0, is_ip4, is_ip6); } else vnet_generic_header_offset_parser (b0, &t->gho, 1, b0->flags & VNET_BUFFER_F_IS_IP4, b0->flags & VNET_BUFFER_F_IS_IP6); clib_memcpy_fast (&t->buffer, b0, sizeof (*b0) - sizeof (b0->pre_data)); clib_memcpy_fast (t->buffer.pre_data, vlib_buffer_get_current (b0), sizeof (t->buffer.pre_data)); } n_added = add_buffer_to_slot (vm, vif, type, vring, buffers[0], free_desc_count, avail, next, mask, do_gso, csum_offload, node->node_index); if (PREDICT_FALSE (n_added == 0)) { buffers++; n_left--; continue; } else if (PREDICT_FALSE (n_added > free_desc_count)) break; avail++; next = (next + n_added) & mask; used += n_added; buffers++; n_left--; free_desc_count -= n_added; } if (n_left != frame->n_vectors) { CLIB_MEMORY_STORE_BARRIER (); vring->avail->idx = avail; vring->desc_next = next; vring->desc_in_use = used; if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0) virtio_kick (vm, vring, vif); } if (n_left) { if (retry_count--) goto retry; virtio_interface_drop_inline (vm, node->node_index, buffers, n_left, VIRTIO_TX_ERROR_NO_FREE_SLOTS); } clib_spinlock_unlock_if_init (&vring->lockp); return frame->n_vectors - n_left; } static_always_inline uword virtio_interface_tx_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, virtio_if_t * vif, virtio_if_type_t type) { vnet_main_t *vnm = vnet_get_main (); vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, vif->hw_if_index); if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO) return virtio_interface_tx_gso_inline (vm, node, frame, vif, type, 1 /* do_gso */ , 1 /* checksum offload */ ); else if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD) return virtio_interface_tx_gso_inline (vm, node, frame, vif, type, 0 /* no do_gso */ , 1 /* checksum offload */ ); else return virtio_interface_tx_gso_inline (vm, node, frame, vif, type, 0 /* no do_gso */ , 0 /* no checksum offload */ ); } VNET_DEVICE_CLASS_TX_FN (virtio_device_class) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { virtio_main_t *nm = &virtio_main; vnet_interface_output_runtime_t *rund = (void *) node->runtime_data; virtio_if_t *vif = pool_elt_at_index (nm->interfaces, rund->dev_instance); if (vif->type == VIRTIO_IF_TYPE_TAP) return virtio_interface_tx_inline (vm, node, frame, vif, VIRTIO_IF_TYPE_TAP); else if (vif->type == VIRTIO_IF_TYPE_PCI) return virtio_interface_tx_inline (vm, node, frame, vif, VIRTIO_IF_TYPE_PCI); else if (vif->type == VIRTIO_IF_TYPE_TUN) return virtio_interface_tx_inline (vm, node, frame, vif, VIRTIO_IF_TYPE_TUN); else ASSERT (0); return 0; } static void virtio_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index, u32 node_index) { virtio_main_t *apm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (apm->interfaces, hw->dev_instance); /* Shut off redirection */ if (node_index == ~0) { vif->per_interface_next_index = node_index; return; } vif->per_interface_next_index = vlib_node_add_next (vlib_get_main (), virtio_input_node.index, node_index); } static void virtio_clear_hw_interface_counters (u32 instance) { /* Nothing for now */ } static clib_error_t * virtio_interface_rx_mode_change (vnet_main_t * vnm, u32 hw_if_index, u32 qid, vnet_hw_interface_rx_mode mode) { virtio_main_t *mm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance); virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid); if (vif->type == VIRTIO_IF_TYPE_PCI && !(vif->support_int_mode)) { vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT; return clib_error_return (0, "interrupt mode is not supported"); } if (mode == VNET_HW_INTERFACE_RX_MODE_POLLING) vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT; else vring->avail->flags &= ~VIRTIO_RING_FLAG_MASK_INT; return 0; } static clib_error_t * virtio_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags) { virtio_main_t *mm = &virtio_main; vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index); virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance); if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) { vif->flags |= VIRTIO_IF_FLAG_ADMIN_UP; vnet_hw_interface_set_flags (vnm, vif->hw_if_index, VNET_HW_INTERFACE_FLAG_LINK_UP); } else { vif->flags &= ~VIRTIO_IF_FLAG_ADMIN_UP; vnet_hw_interface_set_flags (vnm, vif->hw_if_index, 0); } return 0; } static clib_error_t * virtio_subif_add_del_function (vnet_main_t * vnm, u32 hw_if_index, struct vnet_sw_interface_t *st, int is_add) { /* Nothing for now */ return 0; } /* *INDENT-OFF* */ VNET_DEVICE_CLASS (virtio_device_class) = { .name = "virtio", .format_device_name = format_virtio_device_name, .format_device = format_virtio_device, .format_tx_trace = format_virtio_tx_trace, .tx_function_n_errors = VIRTIO_TX_N_ERROR, .tx_function_error_strings = virtio_tx_func_error_strings, .rx_redirect_to_node = virtio_set_interface_next_node, .clear_counters = virtio_clear_hw_interface_counters, .admin_up_down_function = virtio_interface_admin_up_down, .subif_add_del_function = virtio_subif_add_del_function, .rx_mode_change_function = virtio_interface_rx_mode_change, }; /* *INDENT-ON* */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */